Tay-Sachs Test
Serum Hexosaminidase A and B
Why It Is Done
A test to measure hexosaminidase A is done to:
- See whether a newborn has Tay-Sachs disease.
- Find carriers of the Tay-Sachs trait. People of Ashkenazi Jewish or French-Canadian descent who have a family history of Tay-Sachs disease or who live in a community or population with a high amount of Tay-Sachs disease need to be tested for Tay-Sachs trait.
- See whether an unborn baby (fetus) has Tay-Sachs disease. This is done early in pregnancy by amniocentesis or chorionic villus sampling.
If you are considering having a child, the Canadian College of Medical Geneticists and the Society of Obstetricians and Gynaecologists of Canada recommend that:1
- Both prospective parents be screened if both of you are Ashkenazi Jews or of French-Canadian or Cajun descent or have a family history of the disease. If both of you test positive as carriers, you should consider genetic counselling.
- You or your partner be screened if either of you is an Ashkenazi Jew or of French-Canadian or Cajun descent or has a family history of the disease. If one of you tests positive for the trait, the other partner should be screened.
Some provinces in Canada offer Tay-Sachs screening to high school students of Ashkenazi Jewish descent. Later, when women who are carriers are considering pregnancy, their partners should also be tested.2
 Go to previous section |  Go to top of page |  Go to next section |
| Author: | Carrie Henley Jan Nissl, RN, BS | Last Updated: June 20, 2006 |
| Medical Review: | Adam Husney, MD - Family Medicine Michael J. Sexton, MD - Pediatrics Renee H. Martin, PhD - Medical Genetics | |
 | ||
| |
| Topic Contents | |
| Test Overview | |
 | Why It Is Done |
| How To Prepare | |
| How It Is Done | |
| How It Feels | |
| Risks | |
| Results | |
| What Affects the Test | |
| What To Think About | |
| References | |
| Credits | |